Display current time in time/date format combobox

Author: VictoriousRaptor

Flow.Launcher/SettingWindow.xaml

@@ -2169,8 +2169,8 @@
                                                                 Margin="0,0,18,0"
                                                                 VerticalAlignment="Center"
                                                                 FontSize="14"
-                                                                ItemsSource="{Binding TimeFormatList}"
-                                                                SelectedValue="{Binding Settings.TimeFormat}"
+                                                                ItemsSource="{Binding TimeFormatDisplayList}"
+                                                                SelectedIndex="{Binding TimeFormatIndex, Mode=OneTime}"
                                                                 SelectionChanged="PreviewClockAndDate" />
                                                             <ui:ToggleSwitch
                                                                 IsOn="{Binding UseClock, Mode=TwoWay}"
@@ -2207,8 +2207,8 @@
                                                                 Margin="0,0,18,0"
                                                                 VerticalAlignment="Center"
                                                                 FontSize="14"
-                                                                ItemsSource="{Binding DateFormatList}"
-                                                                SelectedValue="{Binding Settings.DateFormat}"
+                                                                ItemsSource="{Binding DateFormatDisplayList}"
+                                                                SelectedIndex="{Binding DateFormatIndex, Mode=OneTime}"
                                                                 SelectionChanged="PreviewClockAndDate" />
                                                             <ui:ToggleSwitch
                                                                 IsOn="{Binding UseDate, Mode=TwoWay}"

Flow.Launcher/SettingWindow.xaml.cs

@@ -7,6 +7,7 @@
 using Flow.Launcher.Plugin;
 using Flow.Launcher.Plugin.SharedCommands;
 using Flow.Launcher.ViewModel;
+using Microsoft.VisualBasic;
 using ModernWpf;
 using ModernWpf.Controls;
 using System;
@@ -516,6 +517,15 @@ private void PluginStore_OnKeyDown(object sender, KeyEventArgs e)
 
         private void PreviewClockAndDate(object sender, RoutedEventArgs e)
         {
+            if (DateFormat != null && TimeFormat != null)
+            {
+                viewModel.UpdateDateTimeDisplayList(DateFormat.SelectedIndex, TimeFormat.SelectedIndex);
+                DateFormat.Items.Refresh();
+                TimeFormat.Items.Refresh(); // selected = -1
+                // todo avoid recursion
+                DateFormat.SelectedIndex = viewModel.DateFormatIndex;
+                TimeFormat.SelectedIndex = viewModel.TimeFormatIndex;
+            }
             ClockDisplay();
         }
 
@@ -556,6 +566,7 @@ public void InitializePosition()
             }
             WindowState = settings.SettingWindowState;
         }
+
         public double WindowLeft()
         {
             var screen = Screen.FromPoint(System.Windows.Forms.Cursor.Position);

Flow.Launcher/ViewModel/SettingWindowViewModel.cs

@@ -21,6 +21,7 @@
 using Flow.Launcher.Plugin.SharedModels;
 using System.Collections.ObjectModel;
 using CommunityToolkit.Mvvm.Input;
+using System.Globalization;
 
 namespace Flow.Launcher.ViewModel
 {
@@ -48,6 +49,13 @@ public SettingWindowViewModel(Updater updater, IPortable portable)
                         break;
                 }
             };
+            int tmp = 0;
+            TimeFormatIndex = (tmp = TimeFormatList.FindIndex(x => x.Equals(Settings.TimeFormat))) >= 0 ? tmp : 0;
+            DateFormatIndex = (tmp = DateFormatList.FindIndex(x => x.Equals(Settings.DateFormat))) >= 0 ? tmp : 0;
+
+            TimeFormatDisplayList = TimeFormatList.Select(x => DateTime.Now.ToString(x, CultureInfo.CurrentCulture)).ToList();
+            DateFormatDisplayList = DateFormatList.Select(x => DateTime.Now.ToString(x, CultureInfo.CurrentCulture)).ToList();
+            UpdateSettingsDateTimeFormat();  // just in case something wrong
         }
 
         public Settings Settings { get; set; }
@@ -422,8 +430,6 @@ public List<ColorScheme> ColorSchemes
             }
         }
 
-
-
         public class SearchWindowPosition
         {
             public string Display { get; set; }
@@ -470,6 +476,40 @@ public List<SearchWindowPosition> SearchWindowPositions
             "dd', 'MMMM"
         };
 
+        public int TimeFormatIndex { get; set; } = 0;
+
+        public int DateFormatIndex { get; set; } = 0;
+
+        public List<string> TimeFormatDisplayList { get; set; } = null;
+
+        public List<string> DateFormatDisplayList { get; set; } = null;
+
+        public void UpdateSettingsDateTimeFormat()
+        {
+            Settings.DateFormat = DateFormatList[DateFormatIndex];
+            Settings.TimeFormat = TimeFormatList[TimeFormatIndex];
+        }
+
+        public void UpdateDateTimeDisplayList(int dateIndex, int timeIndex)
+        {
+            if (dateIndex == -1 || timeIndex == -1) 
+                return;
+            DateFormatIndex = dateIndex;
+            TimeFormatIndex = timeIndex;
+
+            for (int i = 0; i < TimeFormatList.Count; ++i)
+            {
+                TimeFormatDisplayList[i] = DateTime.Now.ToString(TimeFormatList[i], CultureInfo.CurrentCulture);
+            }
+
+            for (int i = 0; i < DateFormatList.Count; ++i)
+            {
+                DateFormatDisplayList[i] = DateTime.Now.ToString(DateFormatList[i], CultureInfo.CurrentCulture);
+            }
+
+            UpdateSettingsDateTimeFormat();
+        }
+
         public double WindowWidthSize
         {
             get => Settings.WindowSize;